The intent is to enhance the usability and usefulness of the Web and its interconnected resources through: documents &quot;marked up&quot; with semantic information (an extension of the HTML <meta> tags used in today's Web pages to supply information for Web search engines using web crawlers). This could be machine-readable information about the human-readable content of the document (such as the creator, title, description, etc., of the document) or it could be purely metadata representing a set of facts (such as resources and services elsewhere in the site). Common metadata vocabularies and maps between vocabularies that allow document creators to mark up their documents so that agents can use the information in the supplied metadata (so that Author in the sense of 'the Author of the page' won't be confused with Author in the sense of a book that is the subject of a book review).